Make `sys.dllhandle` available on non-Windows

[FFY00]

Feature or enhancement

Proposal:

We currently expose the Python library path, if available, as sys.dllhandle on Windows. This could also be helpful on other platforms.

My main worry are hasattr(sys, 'dllhandle') checks that assume its availability on Windows only. @zooba, do you have any concerns about this?

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

[zooba]

I don't think this attribute transfers well to other OS's - it would be the equivalent of returning dlopen(sysconfig.get_config_var("LIBRARY")) (or something like that - I guessed the variable name).

It's most useful for ctypes, which I believe already has a way to get the current Python API?

[FFY00]

Ugh, yes 🤦. What I want is an attribute with the path of the runtime library.

[FFY00]

Opened GH-129492.